MENU

Your dog's nutrition is important for a healthy & happy life. petMD experts help you to know what to feed your dog, how much food to feed, and the differences in dog foods, so your dog gets optimum nutrition.

7 Medical Causes Behind Weight Gain

Hypothyroidism

The thyroid glands are responsible for the production of thyroid hormones, the chief instigator for how quickly the body uses energy. That is, the speed at which energy is metabolized. Energy is taken into the body in the form of food, and under normal health conditions, the body burns this energy during the course of normal activity. However, under production of thyroid hormones can result in a sluggish metabolism, and too much energy being retained in the body, resulting in a burden of weight. The name for this condition is hypothyroidism, where the prefix hypo- means “under.” It can be confounding to observe that even while your pet is eating very little, she is continuing to gain weight. This is because even the small amount of food energy she is taking in is being stored rather than released through the metabolic process.

Some of the other symptoms seen with this disorder are fatigue, coarse hair coat, slow heart rate, and itchy, dry skin. Your veterinarian can conduct some straightforward blood tests to determine if your pet has an underlying case of hypothyroidism. If the diagnosis is positive for hypothyroidism, your doctor can prescribe medication to treat it

Cushing’s Disease (Hyperadrenocorticism)

Often seen in older animals, particularly older dogs, Cushing’s disease is a disorder that arises from long-term overproduction of glucocorticoid hormones, which are an important aspect of protein, carbohydrate, and metabolic regulation. This hormone is related to the adrenal glands (found near the kidneys) and pituitary glands, developing when something in one of these glands is abnormal.

With pituitary Cushing’s, the condition is most often caused by a tumor in the gland that is causing the gland to produce excess ACTH. This is the most common form of Cushing’s. With adrenal Cushing’s, the condition is caused by excess production of cortisol, a steroid hormone. Cushing ’s disease is commonly symptomized by muscle weakness and wasting, extreme thirst, increased appetite, urinary tract infections, rapid weight gain, and hair loss.

One of the most apparent outward symptoms is a potbelly, which is due to the wasting of muscles in the abdomen and the shifting of fat into the abdominal area. If you suspect that your pet has Cushing's disease, you will need to take your pet to a veterinarian for a full blood, urine, and chemistry profile.

Bloat

Some dogs, either because of their background, current living conditions, health or personal characteristic, will eat their food rapidly. This behavior is referred to as “wolfing down” food by some pet owners, and is often remarked upon as appearing as though the dog is swallowing its food without tasting or chewing it – or “gulping” it down. This is, in fact, pretty much what is happening. As the dog “wolfs down” its food, it is also swallowing large amounts of air.

What follows is a stomach full of unchewed food and excess air, resulting in a condition called gastric dilatation and volvulus syndrome (GDV), more commonly referred to as bloat. Besides the obvious distended belly, dogs suffering from bloat will often have symptoms of troubled breathing, rapid heartbeat, pain in the abdomen (on touch), drooling and collapse. This is a life-threatening condition requiring immediate medical attention. Bloat is most often seen in large, deep-chested breeds of dogs, such as Great Danes, German Shepherds, and Standard Poodles.